北极礁膜室内人工育苗的研究

于2004年对大连地区北极礁膜M onostroma arcticum的生物学进行了初步研究,并在室内进行了合子采苗、孢子体培养和孢子采苗及幼苗培养等人工育苗试验。结果表明:水温为3℃时,北极礁膜的叶片长度达到16 cm;水温为5℃时,配子放散量达到2.4×108个/g;孢子体在水温低于19℃时生长较快,水温超过22℃时生长几乎停止。孢子体在度过夏季高温期后,当水温降至20℃以下时,开始形成孢子囊;当水温降至15℃时,孢子放散量达到6.1×105个/cm2;孢子附着到苗绳上后经过50 d的室内培养,培育出长度为1 cm的北极礁膜幼苗。     

Algal-oligosaccharide-lysates prepared by two bacterial agarases stepwise hydrolyzed and their anti-oxidative properties

Twenty algal-oligosaccharide-lysates (AOLs), derived from six agars and four algal polysaccharide extracts (APEs), were treated first with agarases with 250 or 500 agarase activity units (AU), which were produced from the agar-liquefying bacterial strain Pseudomonas vesicularis MA103, named MA103-agarases. The AOLs were then treated with agarases (250 or 500 AU) derived from the agar-softening bacterial strain Aeromonas salmonicida MAEF 108, named MAEF 108-agarases. Anti-oxidative properties of the AOLs were evaluated by five in vitro methods. The AOL obtained from the APE of Porphyra dentate, digested by 250 AU of MA 103-agarases, and by 250 AU of MAEF 108-agarases, designated as A₂₅₀-Por, showed better results than the 19 other AOLs. This result is in accordance with the level of soluble total polyphenols (STP) of A₂₅₀-Por, which was also higher than the remainder of the AOLs tested. The AOL derived from the APE of P. dentate, digested by 500 AU of MA103-agarases and then 500 AU of MAEF108-agarases, and designated as B₅₀₀-Por, displayed the second highest data in four potential evaluation methods, except in H₂O₂ scavenging capacity. In this study, certain agars or APEs digested by specific agarases can present an increasing antioxidative capacity. These agars include Bitek agar, Agar powder, Bacteriological, Agar Bacteriological, and Guanghui agar, plus APEs of Gracilaria sp. and Monostroma nitidum decomposed stepwise by two agarases. The fraction of polyphenols (<1 kDa) that were derived from A₂₅₀-Por showed anti-oxidative activities on α, α-diphenyl-β-picrylhydrazyl (DPPH) assay and reducing power determination, while the remaining four agar-lytic fractions obtained from A₂₅₀-Por did not exhibit anti-oxidative activity. This phenomenon may suggest that anti-oxidative properties of AOLs originate in polyphenols. Algal-oligosaccharide-lysates may have potential use as a health food.     

Preparation of algal-oligosaccharide mixtures by bacterial agarases and their antioxidative properties

ABSTRACT:   Algal-oligosaccharide-lysates (AOL), derived from six agars and four algal polysaccharide extracts (APE), were treated with 100–500 activity units (AU) of MA103-agarases or MAEF108-agarases, and their antioxidative properties evaluated. Soluble total polyphenols (TP) were between 462.2 ± 1.6 gallic acid equivalents (GAE, µg/mL) and 70.6 ± 17.4 GAE. The DPPH radical scavenging capacity of all AOL went from 68.3 ± 0.7% to 0.5 ± 0.1%. The ferrous ion chelating capacity of all AOL went from 93.1 ± 0.2% to 21.7 ± 0.9%. Evaluation of the H₂O₂ scavenging capacity of all AOL was between 35.9 ± 5.4% and 0.1 ± 0.2%. The reducing power of all AOL went from 51.3 ± 2.6 to 3.2 ± 6.8 expressed as µg/mL ascorbic acid. In DPPH radical scavenging capacity, ferrous ion chelating capacity and reducing power etc., the AOL derived from the APE of Porphyra dentate (digested by 500 AU of MAEF108-agarases) were highest, in all test sets. However, the AOL derived from the APE of Monostroma nitidum (digested by 500 AU of MAEF108-agarases) had the highest H₂O₂ scavenging capacity in all test sets. The order of antioxidative activity performance of all AOL treated in this experiment, by these four antioxidative methods, is as follows: ferrous ion chelating capacity > DPPH radical scavenging capacity > H₂O₂ scavenging capacity > reducing power; this may be related to their polyphenols, small molecular weight polysaccharides or simple sugar constituents. In this study, it is demonstrated that various agarases derived from algal oligosaccharide mixtures possess good potential for use as a health food, due to their antioxidative capacity.     

两面针繁殖技术研究

[目的]探索两面针种子繁殖与扦插繁殖技术。[方法]以来自桂林和钦州两面针种子为试材,不处理为CK,研究了试剂处理、砂纸处理、润砂催芽对种子发芽的影响。同时也研究了不同水平的激素种类、激素浓度、处理时间、留叶程度、扦插基质对两地的插穗扦插质量的影响。[结果]不同产地的种子大小和千粒重具有显著差异,钦州的种子好于桂林的;两面针种子具有后熟特性,润砂处理的种子发芽最好,最高发芽率达到80%,冬季扦插效果比夏季好,基质与插穗留叶数量对扦插生根成活影响较大。激素种类对生根条数、生根总长的影响最大。[结论]温度和种子大小影响种子的发芽质量,适宜的留叶数量,扦插基质和枝条有利于扦插繁殖。     

盐度和营养盐对礁膜配子体发育的影响

礁膜(Monostroma nitidum)是我国重要的经济海藻之一,隶属于绿藻门,绿藻纲,石莼目,礁膜科,礁膜属。礁膜广泛分布于我国的东南沿海,生长在内湾静水处的岩石上或具有泥砂的石块上。日常所见的礁膜叶状体是配子体,为膜状,呈绿色或黄绿色,体软并具光泽。礁膜是绿藻中食用价值最高的一种,体软味美,我国南北沿海居民有食用。日本人也喜食“紫菜酱”(原料以礁膜为主,掺入少量紫菜,加入调味料,高压烹煮而成)。此外,礁膜还具有一定的药用价值,如清热化痰,利水解毒以及降低胆     

广西两面针种群分布特征

通过对广西两面针种群资源的实地调查,阐明了两面针在广西的地理分布、生态型分布及种群生境特点;并对两面针有效成分含量与土壤中各营养成分含量的相关性进行分析,结果表明:广西地区两面针有效成分含量仅与土壤有效磷含量成正相关,而与土壤pH值、有机质含量等都呈负相关。     

An improved enzyme preparation for rapid mass production of protoplasts as seed stock for aquaculture of macrophytic marine green algae

Preparation of protoplasts and their subsequent applications for both basic and applied research of marine macroalgae remains largely under developed due to lack of development of reliable methods with consistent yields of viable protoplasts. An improved enzyme preparation with a single commercial enzyme, e.g. 2% Cellulase Onozuka R-10 in 1% NaCl solution, was developed to produce protoplasts rapidly from different green algal genera of Ulva, Enteromorpha and Monostroma. The simple dissolution of enzyme powder in 1% NaCl resulted in exclusion of 2% Macerozyme R-10 from the mixture consisting of 2% Cellulase Onozuka R-10 with 3% NaCl earlier reported as superior for the same algae. Optimal conditions for the isolation of maximum yields of viable protoplasts were found to be with 2% Cellulase Onozuka R-10 incubated at 20 °C for 2 h in 1% NaCl solution with 0.8 M mannitol adjusted to pH 6.0. The protoplast yield with optimized enzyme mixture was as high as 102.8 × 10⁶ cells g^− 1 f. wt for M. oxyspermum while it was in the range of 74.4–88.6 × 10⁶ cells g^− 1 f. wt thallus for seven species of Ulva, and 82.5–95.4 × 10⁶ cells g^− 1 f. wt for three species of Enteromorpha. The regeneration rate of protoplasts isolated using this method ranged from 89 to 92% with normal morphogenesis. The seeding of nylon threads with isolated protoplasts of M. oxyspermum was successful and after 3–4 weeks the entire frame with nylon threads became thick green in color with tiny germlings in laboratory culture. Thus, the method described in the present study allow for rapid mass production of viable protoplasts that could be potentially used as a source for seed material for mariculture and for other applied phycological research.     

光照对礁膜合子生长发育的影响

礁膜配子接合及合子的附着以１０－１２ｈ的黑暗处理为宜。光强对合子的生长发育影响较大，合子早期生长快，适宜光强为３０００－５０００ｌｘ，合子后期生长减慢，开始转化形成游孢子囊，适当降低光照强度和缩短光照时间有利于游孢子囊的形成和游孢子的放散。这些研究结果将为礁膜人工育苗提供科学依据。     

两面针苗木分级标准的研究

运用随机抽样、主成分分析和逐步聚类分析等方法,对两面针当年生苗和1年生苗的分级标准进行调查研究。结果表明,地径和苗高对两面针苗木质量有很好的表达,可以作为苗木分级的质量指标;按照3个等级,提出了两面针当年生苗和1年生苗相应的分级标准;经实测该分级标准与苗木实际情况相符,可为生产提供参考。     

宽礁膜原生质体的分化与发育

为缩短传统育苗时间,开发室内种质保存技术,满足大规模栽培苗种需求,实验用4%的果胶酶和2%纤维素酶混合,将来自于不同月份和不同藻体部位的宽礁膜切段,分别在相同条件下解离成原生质体,详细研究了这些不同部位和不同生长时期细胞的再生、分化和发育途径。根据体细胞后代的外形、有无假根、有无公共膜、细胞大小和排列方式,以及它们最终的发育分化趋势,将宽礁膜原生质体发育方式分为8种结果,既可形成体细胞,也可形成生殖细胞。形成体细胞的发育途径又分3种类型7种结果,即细胞团、畸形苗和正常苗3种类型,其中发育成细胞团的类型又分为规则细胞团和不规则细胞团2种结果,发育成畸形苗的类型又分为假根为主的畸形苗、有类假根的畸形苗、无假根的畸形苗和管状畸形苗4种结果。各种发育类型与藻体的日龄、大小及部位有关,其原生质体直接发育形成正常形态藻体的发育方式只是8种发育结果的一种。